The first statement refers to oviously objects hidden anywhere else but the ground . Thats why they need to sniff in the air for obvious reasons unless they are barking ( no pun intended ) at te wrong tree .
On the second statement , its contrary to the TRACKING . Nag libog pod ko if ever ang object was hidden in a cabinet . How will the dog actually find that object ? Unless mo patong sila ug lababo via ladder or a table regardless if asa sila nag sniff , sa air or sa ground ba . .